Answer:   HttpHandler is a low level request and response API which is made to service incoming Http request. Every incoming Http request recieved by ASP.NET is ultimately processed by a instance of a class that implements HttpHandler.

Answer:   HTTPHandler is a low level request and response API in ASP.Net for injecting pre-processing logic to the pipeline based on file extensions and verbs. An HTTPhandler may be defined as an end point that is executed in response to a request and is used to handle specific requests based on extensions.